// Copyright (c) 2012 Ecma International. All rights reserved. // Ecma International makes this code available under the terms and conditions set // forth on http://hg.ecmascript.org/tests/test262/raw-file/tip/LICENSE (the // "Use Terms"). Any redistribution of this code must retain the above // copyright and this notice and otherwise comply with the Use Terms. /*--- description: > Strict Mode - TypeError is thrown if The LeftHandSide of a Compound Assignment operator(-=) is a reference to a non-existent property of an object whose [[Extensible]] internal property if false flags: [onlyStrict] includes: [runTestCase.js] ---*/ function testcase() { "use strict"; var obj = {}; Object.preventExtensions(obj); try { obj.len -= 10; return false; } catch (e) { return e instanceof TypeError; } } runTestCase(testcase);